Colliders for pre-placed trees?

I’ve read many pages or this ‘walking through trees’ topic but never could find a solution for pre-placed trees. Now the normal way to do this is to add the capsule or mesh collider to the tree, them paint them on terrain or place them by hand. But I’m wondering if you could do this to trees that were placed (with the terrain paint thing) without a capsule/mesh collider?22662-trees.png

That’s the same as “…place them by hand”; so yes, you can create your own collider/script and place them around the trees. If that’s not what you were asking, please clarify

the trees (pictured) were placed without any sort of colliders with the terrain tree painter thing. i was wondering if there’s a way to add colliders to them without replacing all the trees.